Added placeholder settings for fast iteration (#8)

## Description

This pull request adds configuration options to the
`.github/PSModule.yml` file to allow skipping various test and build
steps. These changes make it easier to customize which checks and builds
are run in CI.

Configuration changes for skipping steps:

* Added options to skip test results, source code checks, and PowerShell
module checks in the `Test` section.
* Added options to skip Windows and MacOS module checks under the
`Module` section.
* Added an option to skip documentation builds in the `Build` section.

## Type of change

<!-- Use the check-boxes [x] on the options that are relevant. -->

- [ ] 📖 [Docs]
- [ ] 🪲 [Fix]
- [x] 🩹 [Patch]
- [ ] ⚠️ [Security fix]
- [ ] 🚀 [Feature]
- [ ] 🌟 [Breaking change]

## Checklist

<!-- Use the check-boxes [x] on the options that are relevant. -->

- [x] I have performed a self-review of my own code
- [x] I have commented my code, particularly in hard-to-understand areas

Author: MariusStorhaug

.github/PSModule.yml

@@ -5,3 +5,17 @@
 Test:
   CodeCoverage:
     PercentTarget: 0
+#   TestResults:
+#     Skip: true
+#   SourceCode:
+#     Skip: true
+#   PSModule:
+#     Skip: true
+#   Module:
+#     Windows:
+#       Skip: true
+#     MacOS:
+#       Skip: true
+# Build:
+#   Docs:
+#     Skip: true